Prosecution Insights
Last updated: April 19, 2026
Application No. 18/279,528

GADOLINIUM CHELATE, PREPARATION METHOD THEREFOR, AND APPLICATION THEREOF

Non-Final OA §102§103
Filed
Aug 30, 2023
Examiner
PACKARD, BENJAMIN J
Art Unit
1612
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
South Medical University
OA Round
1 (Non-Final)
66%
Grant Probability
Favorable
1-2
OA Rounds
2y 11m
To Grant
82%
With Interview

Examiner Intelligence

Grants 66% — above average
66%
Career Allow Rate
869 granted / 1317 resolved
+6.0% vs TC avg
Strong +16% interview lift
Without
With
+16.1%
Interview Lift
resolved cases with interview
Typical timeline
2y 11m
Avg Prosecution
44 currently pending
Career history
1361
Total Applications
across all art units

Statute-Specific Performance

§101
1.1%
-38.9% vs TC avg
§103
44.2%
+4.2% vs TC avg
§102
18.6%
-21.4% vs TC avg
§112
14.5%
-25.5% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1317 resolved cases

Office Action

§102 §103
DETAILED ACTION Notice of Pre-AIA or AIA Status The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . Claim Rejections - 35 USC § 102 In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status. The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. Claims 1-2, and 12 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by CN 10140943 A, hereinafter CN ‘943. CN ‘943 discloses a gadolinium (III) chelate produce by the reaction of oligomeric ethylenediamine-N,N’-bis(acetanilide)-diactate with GdCl3 aqueous solution, with a molecular weight of 2885 (Example 1). The chelate is disclosed to have lower toxicity, good biocompatibility and improved stability as a contrast agent (description and pg 2 ¶ 3). Claims 1-3, and 12 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Unaleroglu et al (J of Appl Polymer Sci, v 56, no 10, 1239-1243, 1995). Unaleroglu et al discloses a PAA aqueous solution having a molecular weight of 230,000 produced by reacting a metal nitrate solution to obtain gadolinium(III)-PAA chelate (Experiment, ¶ 1, Table 1, and solution 1). Claims 1, 4, and 21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Hummel et al (US 20090238767). Hummel et al discloses gadolinium chelated to polylysine was well known as imaging agents abstract and (¶ 45). Claims 1, 5-8, and 21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Yokoyama et al (Magn Reson Mater Phy 33, 527–536 2020). Yokoyama et al discloses known Gd chlelates for macromolecular MRI contrast agents include chelates of polyserine, polylactic, PEG, and polyglutamine (pg 532 Table 2, . Claims 1-2, 9, and 21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by CN 111643684 A, hereinafter CN ‘684. CN ‘684 discloses gadolinium chelated to human proteins for use as contrast agents (abstract, Example 1, and claim 1). Claims 1-2, 9-10, and 21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated Zhou et al (Wires, Nanomedicien and Nanibiotechnology, V 5, Iss 1, 2013, 1-18). Zhou et al discloses gadolinium chelated to RGD peptides (see Tumor-Targeting Small Molecular Gd(III) CA). Claims 1-2, 11, and 21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated Podgorna et al (Colloids and Surfaces B: Biointerfaces Volume 153, 1 May 2017, Pages 183-189). Podgorna et al discloses gadolinium alginate nanogels. Claim Rejections - 35 USC § 103 The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action: A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made. The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows: 1. Determining the scope and contents of the prior art. 2. Ascertaining the differences between the prior art and the claims at issue. 3. Resolving the level of ordinary skill in the pertinent art. 4. Considering objective evidence present in the application indicating obviousness or nonobviousness. This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention. Claims 1-2, 12, and 14-21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by CN 10140943 A, hereinafter CN ‘943. The reference is discussed above, but does not teach the specific molarity for forming the chelates. Where the prior art teaches the components to formulate the chelates, it would have been obvious to one of ordinary skill in the art to vary the amount of each component to produce the desired reaction. Claims 1-3, 12, and 14-21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Unaleroglu et al (J of Appl Polymer Sci, v 56, no 10, 1239-1243, 1995). The reference is discussed above, but does not teach the specific molarity for forming the chelates. Where the prior art teaches the components to formulate the chelates, it would have been obvious to one of ordinary skill in the art to vary the amount of each component to produce the desired reaction. Claims 1, 4, and 14-21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Hummel et al (US 20090238767). The reference is discussed above, but does not teach the specific molarity for forming the chelates. Where the prior art teaches the components to formulate the chelates, it would have been obvious to one of ordinary skill in the art to vary the amount of each component to produce the desired reaction. Claims 1, 5-8, and 14-21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Yokoyama et al (Magn Reson Mater Phy 33, 527–536 2020). The reference is discussed above, but does not teach the specific molarity for forming the chelates. Where the prior art teaches the components to formulate the chelates, it would have been obvious to one of ordinary skill in the art to vary the amount of each component to produce the desired reaction. Claims 1-2, 9, and 14-21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by CN 111643684 A, hereinafter CN ‘684. The reference is discussed above, but does not teach the specific molarity for forming the chelates. Where the prior art teaches the components to formulate the chelates, it would have been obvious to one of ordinary skill in the art to vary the amount of each component to produce the desired reaction. Claims 1-2, 9-10, and 14-21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated Zhou et al (Wires, Nanomedicien and Nanibiotechnology, V 5, Iss 1, 2013, 1-18). The reference is discussed above, but does not teach the specific molarity for forming the chelates. Where the prior art teaches the components to formulate the chelates, it would have been obvious to one of ordinary skill in the art to vary the amount of each component to produce the desired reaction. Claims 1-2, 11, and 14-21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated Podgorna et al (Colloids and Surfaces B: Biointerfaces Volume 153, 1 May 2017, Pages 183-189). The reference is discussed above, but does not teach the specific molarity for forming the chelates. Where the prior art teaches the components to formulate the chelates, it would have been obvious to one of ordinary skill in the art to vary the amount of each component to produce the desired reaction. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to BENJAMIN J PACKARD whose telephone number is (571)270-3440. The examiner can normally be reached Mon 2-6pm and Tues-Fri (9am-6pm + mid-day flex). Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sahana S. Kaup can be reached at (571) 272-6897. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /BENJAMIN J PACKARD/ Primary Examiner, Art Unit 1612
Read full office action

Prosecution Timeline

Aug 30, 2023
Application Filed
Feb 06, 2026
Non-Final Rejection — §102, §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12589111
PT(IV) CHEMOTHERAPEUTIC PRODRUG AND CONTROLLED RELEASE THEREOF FOR TREATMENT OF TUMORS
2y 5m to grant Granted Mar 31, 2026
Patent 12582745
ADHESIVE COMPOSITION FOR HARD TISSUE REPAIR
2y 5m to grant Granted Mar 24, 2026
Patent 12583865
Biologically Active Taxane Analogs and Methods of Treatment by Oral Administration
2y 5m to grant Granted Mar 24, 2026
Patent 12582586
Oral Care Compositions
2y 5m to grant Granted Mar 24, 2026
Patent 12576105
COMPOSITIONS FOR TREATING JOINT OR CONNECTIVE TISSUE DISEASE COMPRISING DEXTRAN OR POLOXAMER
2y 5m to grant Granted Mar 17, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

1-2
Expected OA Rounds
66%
Grant Probability
82%
With Interview (+16.1%)
2y 11m
Median Time to Grant
Low
PTA Risk
Based on 1317 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month